Umar Ahmad, Abaker M, Faisal M, Hwang S W, Baskoutas S, Al-Sayari S A
Advanced Materials and Nano-Engineering Laboratory (AMNEL), Centre for Advanced Materials and Nano-Engineering (CAMNE), Najran University, P.O. Box 1988, Najran 11001, Kingdom of Saudi Arabia.
J Nanosci Nanotechnol. 2011 Apr;11(4):3474-80. doi: 10.1166/jnn.2011.4148.
In this paper, the high-yield facile synthesis, detailed characterization and photocatalytic application of alpha-Fe2O3 nanoparticles are reported. The synthesis was done via simple hydrothermal process by using aqueous mixtures of iron chloride, hexamethylenediamine and NH3 x H2O at 110 degrees C. The morphologies of the synthesized products were examined by using field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) which confirmed that the synthesized structures are almost spherical shaped nanoparticles with the average diameters of -35 +/- 5 nm, and are grown in high yield. The detailed structural characterizations and composition of the as-synthesized nanoparticles were investigated by using X-ray diffraction (XRD), high-resolution TEM (HRTEM), energy dispersive spectroscopy (EDS) attached with FESEM and Fourier transform infrared spectroscopy (FTIR) which substantiated that the as-synthesized nanoparticles are well crystalline and pure alpha-Fe2O3. The UV-Vis absorption spectrum of the synthesized nanoparticles demonstrated the existence of two optical band gaps which correspond to direct and indirect transitions, respectively. The as-synthesized alpha-Fe2O3 nanoparticles exhibit good photocatalytic properties on photocatalytic degradation of methylene blue.
本文报道了α-Fe2O3纳米颗粒的高产率简便合成、详细表征及光催化应用。合成过程通过简单的水热法进行，使用氯化铁、六亚甲基二胺和氨水的水性混合物在110℃下反应。利用场发射扫描电子显微镜（FESEM）和透射电子显微镜（TEM）对合成产物的形貌进行了检查，结果证实合成的结构几乎是平均直径为-35±5nm的球形纳米颗粒，且产率很高。通过X射线衍射（XRD）、高分辨率TEM（HRTEM）、与FESEM联用的能量色散光谱（EDS）和傅里叶变换红外光谱（FTIR）对合成的纳米颗粒进行了详细的结构表征和组成研究，证实合成的纳米颗粒结晶良好且为纯α-Fe2O3。合成纳米颗粒的紫外可见吸收光谱表明存在两个光学带隙，分别对应直接跃迁和间接跃迁。合成的α-Fe2O3纳米颗粒在光催化降解亚甲基蓝方面表现出良好的光催化性能。
